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A Moderate Resolution Imaging Spectroradiometer image from NASA's Terra satellite shows Typhoon Neoguri in the Pacific Ocean, approaching Japan on its northward journey on July 6.

Japan on Alert as Weakened Typhoon Neoguri Stays on Course

Churning toward Japan's Okinawa Island, Typhoon Neoguri is expected to bring strong, damaging winds and a dangerous surge on Tuesday local time (late Monday ET), as the country's weather agency urged people in the target areas to evacuate early.

When Typhoon Neoguri's winds reached an estimated 150 mph Sunday, the Joint Typhoon Warning Center dubbed it a "super typhoon." But the winds dropped to 125 mph late Monday morning U.S. time, causing Neoguri to weaken and lose the "super" status. The storm was not expected to be as strong as Typhoon Haiyan, which killed thousands in the Philippines last year.

Okinawa houses three-quarters of U.S. military facilities in Japan. There are no nuclear plants on that island but there are two on Kyushu Island, where Neoguri was expected to make landfall. Shikoku Island, which borders Kyushu, also has a nuclear facility.